Project Number: 5205
Batch Solution Heat Treat Furnace with Integrated Hot Water Quench
Overview
Precision Quincy engineered a batch solution heat treat furnace with integrated hot water quench to support high-integrity aluminum heat treatment across wrought and cast alloys. The system is designed to process up to 1,000 lb per batch on a WIRCO 54 in x 54 in tray with up to 54 in of load height, enabling solution treatment across a wide operating envelope -- 870F to 990F for common wrought alloys (6061, 6063, 7075, and 2024 tempers) and 538C (approx. 1,000F) for 8356 cast alloy -- followed by rapid quench transfer to preserve metallurgical integrity.
To protect metallurgical results, the furnace integrates a rapid transfer mechanism that moves the tray from the hot chamber to the quench within a 10-second maximum allowable transfer window. Loads are staged by forklift on a carriage positioned above the quench tank; a furnace-side hook/gravity engagement feature pulls the tray onto a roller hearth for processing, and a rear-mounted pusher/extractor (8 in/sec, 105 in stroke) transfers the tray back onto the carriage at cycle completion before the carriage submerges the load into the quench. After the prescribed quench dwell, the carriage raises for forklift removal and the sequence repeats.
The furnace is an NFPA 86 Class B, electric design with 144 kW of installed heat using individual 3 kW elements. Convection performance is delivered by a New York Blower 18 in PLR recirculation fan rated at 7,500 CFM at 3.0 in. w.c. with a 7.5 HP motor, producing approximately 4,000 FPM air velocity at the product and supporting +/-10F air temperature uniformity. The hot water quench system includes a 1,900-gallon tank (316 stainless steel with 304 stainless interior), 36 kW electric immersion heat, and an air-to-water cooling system capable of rejecting 575,000 BTU/hr. System controls are based on an Allen-Bradley CompactLogix PLC with SSI 804 temperature control for both furnace and quench subsystems.
The hot water quench system is sized for thermal stability and repeatability with a 1,900-gallon tank (316 stainless steel tank with 304 stainless interior), 36 kW immersion electric heat, and an air-towater cooling system capable of rejecting 575,000 BTU/hr. The quench operates across 150°F to 200°F with a typical setpoint basis of 180°F, using pumped forward-flow agitation with all stainless steel piping. The insulated furnace shell uses a painted 3/16 in mild steel exterior with structural reinforcement and a 304 stainless interior liner, backed by 2 in (8 lb) ceramic wool plus 6 in (6 lb) mineral wool insulation.
The customer required a solution heat treatment system for aluminum parts (wrought and cast) with rapid transfer to a hot water quench.
PROCESS OBJECTIVE (SOLUTION HEAT TREAT + QUENCH)
- Heat treat aluminum loads to alloy-specific solution treatment conditions.
- Transfer the load to a hot water quench within the allowable transfer window.
- Note: After solution treatment, parts typically proceed to a separate aging process in other equipment (not part of this system).
ALLOYS / TEMPERS TO BE PROCESSED (WROUGHT)
- 6061-T6
- 6063-T6
- 7075-T6
- 2024-T3
- 2024-T4
SOLUTION TREATMENT TEMPERATURE RANGE (WROUGHT)
- 870°F to 990°F (alloy-dependent).
CYCLE TIME (WROUGHT)
- Maximum cycle/soak time basis: up to 7 hours (product/alloy-dependent).
CAST ALLOY PROCESS REQUIREMENT
- Alloy: 8356 (cast).
- Solution treatment temperature: 538°C (≈ 1,000°F).
- Time at temperature: 6 to 12 hours.
BATCH / LOAD CAPACITY
- Maximum batch weight: 1,000 lb per batch.
LOAD CARRIER / ENVELOPE
- Load carrier: WIRCO solution heat treat tray (customer-provided).
- Customer tray size: 54 in × 54 in.
- Maximum load height above tray: 54 in.
- Load handling: tray staged and removed via forklift.
QUENCH REQUIREMENTS
- Quench medium: water.
- Water temperature range (hot quench): 150°F to 200°F.
- System setpoint basis: 180°F.
- Maximum allowable transfer time to water (total): 10 seconds.
These thermal process requirements were developed to meet the customer's solution heat treat and quench process needs, based on the application conditions and operating parameters.
OPERATING TEMPERATURE ENVELOPE
- Maximum equipment temperature capability: up to 1,100°F.
- Operating setpoints are alloy- and property-dependent, based on the required solution treatment conditions.
- Setpoint range basis: 870°F to 990°F for wrought alloys; 538°C (≈ 1,000°F) for 8356 cast alloy.
HEATING / SOAK PERFORMANCE
- Must support long-duration solution treatment cycles: up to 7 hours for wrought loads, and 6–12 hours for 8356 cast alloy.
- Required heat-up / ramp-to-soak time: variable (product/load-weight dependent).
AIRFLOW DELIVERY (CONVECTION PERFORMANCE)
- Air velocity at the product: 4,000 FPM blowing on the side of the part.
- Air temperature uniformity: ±10°F.
QUENCH TRANSFER PERFORMANCE (THERMAL-CRITICAL TIMING)
- Maximum allowable transfer time from furnace discharge to quench immersion: 10 seconds (customer basis).
QUENCH THERMAL CONDITIONS (INTERFACE REQUIREMENT)
- Hot water quench temperature control range: 150°F to 200°F; setpoint basis 180°F.
- Quench tank agitation basis: pumped/forward-flow agitation.
To deliver the thermal process requirements (which deliver the customer process requirements), Precision Quincy settled on the following equipment concept and architecture.
OVERALL CONCEPT
- Batch, recirculating solution heat treat furnace with rapid discharge to hot water quench.
- Furnace configured to support alloy-dependent setpoints with a maximum equipment capability of 1,100°F.
- Load handling based on WIRCO 54 in × 54 in trays staged by forklift onto the quench carriage.
MATERIAL FLOW / TRANSFER MECHANISM
- Load is staged on a quench carriage positioned above the tank.
- A furnace-side hook/gravity engagement feature captures the tray and pulls it onto a roller hearth inside the furnace for processing.
- At cycle completion, a rear-mounted pusher/extractor pushes the tray forward onto the carriage.
- Carriage lowers into the quench to allow the pusher dog to disengage; pusher retracts; furnace door closes.
- After the prescribed quench dwell, the carriage raises for forklift removal and the sequence repeats.
HEATING SYSTEM (ELECTRIC)
- Total installed heat input: 144 kW.
- Heating elements: individual 3 kW electric heating elements.
RECIRCULATION / CONVECTION SYSTEM
- Recirculation fan: New York Blower (NYB) 18 in PLR.
- Airflow: 7,500 CFM at 3.0 in. w.c.
- Motor: 7.5 HP.
QUENCH TANK SYSTEM (HOT WATER QUENCH)
- Tank capacity: 1,900 gallons.
- Tank construction: 316 stainless steel with 304 stainless interior.
- Water heating: 36 kW electric, immersion heaters.
- Water cooling: 575,000 BTU/hr heat rejection, air-to-water cooler (5,000 CFM airflow basis).
- Agitation: Pumped forward-flow; 48 GPM pump, 65 ft TDH, 1.5 HP motor; all stainless steel piping.
- Temperature control: SSI 804 (quench tank controller).
DOOR SYSTEM
- Pneumatically powered vertical lift door.
PUSHER / EXTRACTOR SYSTEM
- Location: rear-mounted behind the furnace.
- Push speed: 8 in/sec; stroke length: 105 in.
CONSTRUCTION / SHELL
- Exterior shell: 3/16 in mild steel, two-part epoxy paint, with structural steel reinforcement.
- Wall construction: 8 in total; interior liner 304 stainless steel pans.
- Insulation: 2 in ceramic wool (8 lb/ft³) hot-face plus 6 in mineral wool (6 lb/ft³) backup.
CONTROLS ARCHITECTURE
- PLC / system controls: Allen-Bradley CompactLogix.
- Temperature controller (furnace and quench): SSI 804.
- Airflow proving: airflow switch on recirculation fan.
- High temperature limit: workroom area high limit.
| FURNACE CONFIGURATION | |
|---|---|
| Type | Batch solution heat treat furnace with rapid transfer to hot water quench |
| Process | Solution heat treating aluminum; quench in hot water; aging performed in separate equipment |
| Maximum Equipment Temperature | 1,100°F |
| Typical Operating Setpoints (Wrought) | 870°F to 990°F (alloy-dependent) |
| Cast Alloy Requirement | 8356 (cast) at 538°C (≈ 1,000°F) for 6–12 hours |
| Maximum Batch Weight | 1,000 lb |
| Load Carrier | WIRCO solution heat treat tray |
| Tray Size | 54 in × 54 in |
| Maximum Load Height Above Tray | 54 in |
| Maximum Cycle / Soak Time (Wrought) | Up to 7 hours (product/alloy-dependent) |
| Working / Hearth Dimensions | 54 in W × 54 in L × 54 in H |
| Overall Equipment Dimensions | 243 in D × 115 in W × 250 in H |
| THERMAL SYSTEM (ELECTRIC HEATING + CONVECTION) | |
|---|---|
| Heat Source | Electric |
| Total Installed Heat Power | 144 kW |
| Heating Elements | 3 kW individual electric elements |
| Recirculation Fan | New York Blower (NYB) 18 in PLR |
| Fan Airflow | 7,500 CFM |
| Fan Static Pressure | 3.0 in. w.c. |
| Fan Motor | 7.5 HP |
| Air Velocity at Product | 4,000 FPM (blowing on side of part) |
| Air Temperature Uniformity | ±10°F |
| Temperature Controller (Furnace) | SSI 804 |
| Number of Control Zones | 1 |
| QUENCH TANK SYSTEM (HOT WATER) | |
|---|---|
| Quench Medium | Water |
| Water Temperature Range | 150°F to 200°F |
| Water Setpoint Basis | 180°F |
| Tank Capacity | 1,900 gallons |
| Tank Construction | 316 stainless steel tank with 304 stainless interior |
| Water Heating | 36 kW electric heat, immersion heaters |
| Water Cooling | 575,000 BTU/hr heat rejection, air-to-water cooler |
| Cooler Airflow Basis | 5,000 CFM |
| Water Circulation / Agitation | Pumped forward-flow agitation |
| Water Pump | 48 GPM, 65 ft TDH, 1.5 HP |
| Water Piping | All stainless steel |
| Temperature Controller (Quench) | SSI 804 |
| TRANSFER / HANDLING SYSTEM | |
|---|---|
| Loading / Unloading | Forklift handling of WIRCO tray on quench carriage |
| Maximum Allowable Transfer Time to Water | 10 seconds (total) |
| Furnace Door | Pneumatically powered vertical lift door |
| Hearth / Internal Support | Roller hearth (tray pulled into furnace) |
| Tray Engagement | Hook/gravity engagement feature |
| Pusher / Extractor | Rear-mounted; pushes tray to carriage at cycle completion |
| Pusher Speed | 8 in/sec |
| Pusher Stroke Length | 105 in |
| Carriage Mechanism | A-frame style carriage on engineering chain, pneumatically operated |
| CONSTRUCTION MATERIALS | |
|---|---|
| Exterior Shell | 3/16 in mild steel, two-part epoxy paint |
| Structural Reinforcement | Structural steel reinforcement on shell |
| Interior Liner | 304 stainless steel pans |
| Wall Thickness | 8 in total |
| Hot-Face Insulation | 2 in ceramic wool, 8 lb/ft³ density |
| Backup Insulation | 6 in mineral wool, 6 lb/ft³ density |
| SAFETY & COMPLIANCE | |
|---|---|
| NFPA 86 Classification | Class B |
| Heat Source | Electric |
| Explosion Relief | Not required (NFPA 86 Class B, electric) |
| Airflow Proving | Airflow switch on recirculation fan |
| High Temperature Limits | High limit in workroom area |
| CONTROLS & ELECTRICAL | |
|---|---|
| Power | 480 V / 3 phase / 60 Hz |
| PLC / System Controls | Allen-Bradley CompactLogix |
| Temperature Controller (Furnace) | SSI 804 |
| Temperature Controller (Quench Tank) | SSI 804 |
